General Information: The SALSA MLPA Probemixes P251-P252-P253 Neuroblastoma mix 1-3 are a
research use only (RUO) assays for the detection of copy number changes of several chromosomal regions that frequently show copy number changes in neuroblastoma tumours.
Neuroblastoma (NB) is a relatively common paediatric cancer that usually occurs sporadically and frequently originates from one of the adrenal glands. Neuroblastoma is characterized by striking clinical heterogeneity, including cases that show spontaneous tumour regression. Neuroblastoma accounts for 6-8% of all cancers in children. Several acquired genetic alterations such as amplification of the
MYCN oncogene, deletions of chromosome bands 1p36 and 11q23 and unbalanced gains of 17q regions have been well-characterized and show correlation with tumour behaviour, including response to treatment.
Probemix content: The P251 probemix contains 36 probes in total for chromosomes 1, 3 and 11. The P252 probemix contains 34 probes in total for chromosomes 2 (
MYCN region) and 17, and the P253 probemix contains 33 probes in total for chromosomes 4, 7, 9, 12 and 14. In addition, 13 reference probes are included in P251, 15 reference probes are included in P252 and 14 reference probes are included in P253, which all detect different autosomal chromosomal locations which are relatively stable in their copy number in neuroblastoma. However, it should be noted that neuroblastoma karyotypes can harbour multiple numerical and structural aberrations, which can complicate interpretation of these reference probes. Complete probe sequences and the identity of the genes detected by the reference probes is available online (
www.mlpa.com).
The P251 probemix contains probes for chromosomes 1, 3 and 11:
The P252 probemix contains probes for chromosomes 2 and 17:
The P253 probemix contains probes for chromosomes 4, 7, 9, 12 and 14:
These probemixes contains nine quality control fragments generating amplification products between 64 and 121 nt: four DNA Quantity Fragments (Q-fragments), two DNA Denaturation Fragments (D-fragments), one benchmark fragment, and one chromosome X and one chromosome Y-specific fragment (see table in the product description). More information on how to interpret observations on these control fragments can be found in the MLPA General Protocol and online at
www.mlpa.com.
P252 competitor mix information
Samples with very high levels of MYCN amplification exhibit very high signals for the MYCN probes and low signals for other probes, making it difficult to analyse the latter. Therefore, the P252 probemix is shipped together with a vial of the P252 competitor mix. When a sample shows a very high level of MYCN amplification it can be retested with the competitor mix. This competitor mix contains oligonucleotides that can be included at the start of the MLPA reaction. Adding the competitors specifically reduces the signal of the eight MYCN region probes, making it possible to examine changes in other genes/chromosomal areas.
Instructions for use:
Denature 4 µl sample DNA by heating 5 minutes at 98°C.
Add 1.5 µl MLPA Buffer + 1.5 µl P252 probemix + 1 µl of P252 competitor mix.
Proceed with the MLPA protocol starting with one minute incubation at 95°C and 16 hour incubation at 60°C followed by the ligation and PCR steps.